The application of fluidized catalyst techniques, developed particularly in the petroleum industry for effecting chemical reaction embodying the distribution of heat and/or the disposal of undesired heat, has long been accepted as a major processing tool of the industry. For example, fluidized catalyst techniques have been particularly useful for catalytic cracking of oil vapors to produce lower boiling products and regeneration of the catalyst used in such an operation. It has also been proposed to use the fluidized catalyst technique, primarily for the disposal of generated heat, in the highly exothermic reactions of Fischer-Tropsch synthesis and the known Oxo process and in other such exothermic processes. In the fluidized catalyst operations previously developed, disposal of the reaction heat has been accomplished by many different techniques including transfer of catalyst through cooling sections and/or indirect cooling means with liquids or a fluid catalyst to absorb reaction heat transferred directly or indirectly by the finely divided fluidized catalyst particles. Not only are these prior art catalyst techniques used for temperature control by addition and/or removal of heat, but they have also been found useful for maintaining selective conversions and extending the active life of the catalyst used in the process.
The present invention is concerned with an arrangement of apparatus and method of operation employing a fluid catalyst system in which methanol and related oxygenates are converted particularly to dimethyl ether and hydrocarbons in an upflowing catalyst phase system comprising relatively diluted and more dense phase systems. The exothermic heat of reaction is utilized as hereinafter disclosed to provide product selectivity and prolong the useful life of the catalyst employed in the chemical conversion operation. U.S. Pat. Nos. considered in the preparation of this application include 2,373,008; 3,480,408; 3,969,426; 4,013,732; 4,035,430; 4,044,061; 4,046,825; 4,052,479; 4,071,573 and 4,118,431.